Adjustable trestle



(No Model.) I w E. OWE-N.

ADJUSTABLE TRESTLE.

No. 300,887. Patented June 24,1884

INVENTOR WITNESSES: v Mimmwm.

ATTORNEYS.

lJNrrED STATES PATENT Orrrcs.

EDWARD OWEN, OF JACKSON, TENNESSEE.

\ ADJUSTABLE TRESTLE.

SPECIFICATION forming part of Letters Patent No. 300,887, dated June 24,1884.

Application filed April 7, 1884.

To wZZ whom it may concern;

Be it-known that I, EDWARD OWEN, of J ackson, in the county of Madisonand State of Tennessee, have invented a new and Improved AdjustableTrestle, of which the following is a full, clear, and exact description.

My invention relates to trestles for supporting scaffolding for the useof carpenters, bricklayers, and others; and it consists of a trestlehaving a slotted top bar and a mortised longitudinal beam placed belowthe said bar and adapted to receive a frame, whose side bars areprovided with internal ratchet-teeth, which are engaged by pawls pivotedto the longitudinal bar, the said frame being provided with a centralbar having a series. of transverse pins for receiving a lever employedto raise the frame in the trestle.

Reference is to be had to the accompanying drawings, forming part ofthis specification, in

which similar letters of reference indicate corresponding'parts in allthe figures.

. Figure 1 is a side elevation of my improvec trestle. Fig. 2 is an endelevation, and Fig. 3 is a detail view of the lever employed to operatethe trestle.

The trestle formed of a slotted top bar, A, supported by divergent legsB, is provided with a longitudinal beam, 0, which is secured between thelegs B a short distance from the top bar, A, and ;'parallel with it. Thebeam O is mortised to receive the vertical bars a a and b of the frameD, which passes through the slot of the top bar, A. The bars a a and bare connected at the bottom to a bar, a, and at the top to a bar, cl,which is prolonged at one end beyond the side bar of the frame. A block,E, corresponding in width and thickness to the bar (1, is secured to thetop bar, A, at the side of the frame D. The prolongation of the bar (Zsupports the scaffolding used in connection with the trestle over theextreme (No model.)

which are engaged by oppositely arranged pawls, f, hinged to the beam 0,and capable of resting against shoulders formed on the said beam The barI) is located centrally in the frame D, and extends through the slot inthe top bar, A, and through a mortise in the beam 0, and is providedwith a series of pins,,h, passing through the bar and projecting equallyon each side thereof. The pins are engaged by a forked lever, G, whichis tilted on the bar Fas a fulcrum, and is employed in raising the frameD. As a safeguard in lowering the frame D, a rope, H, secured to the bara, and extending upward through the mortise in the beamO and through ahole, 2', in the top bar, A, is employed. This rope in use is to bepassed around the bar F. When the frame D is lowered or raised by theengagement of the forked lever G with one of the pins, the

frame D is retained at the required height by the engagement of thepawls f with the notches e in the side bars, a a. Holes j are placed atsuitable distances in the bars a a to receive pins k, which pass throughthe said bars and rest upon the slotted top bar, A. The pins are securedto the trestle by means of a flexible cord, so as to be always at handand ready for use. The legs 13 are provided with casters Z, which permitof moving the trestle eas ily in one direction or the other.

My improved scaffold is particularly adapt-- ed to the use ofcarpenters, painters, and bricklayers, and may be raised or loweredwhile the workmen are supported by the scaffolding without interferingwith their work.

I am aware that the vertically-adjustable bars of a trestle have beenprovided with teeth,

with which teeth cog-wheels on a transverse shaft on thesupporting-frame meshed; also, that a transverse shaft was arranged onthe said frame, said shaft having pawls for engaging the teeth; also,that thecentral bar of the vertically-adjustable trestle frame has beenprovided with teeth for engaging a pinion on a shaft on the frame foruse in raising the trestle, these adjustable bars passed through aslotted cross-bar on theframe. Having thus described my invention, Iclaim as new and desire to secure by Letters Patent- 1. The combination,with a trestle provided with a slotted top bar, A, and mortised beam 0,formed with shoulders g, of aframe, D, hav- .3. The frame D, providedwith a. bar, I having notched side bars, a a, and the pawls f, 'ingtransverse pins 71, a trestle adapted to suphinged to the beam 0, andcapable of engagport the frame D, and provided with a bar, ing thenotches of the barsa a at their free F, and the forked lever G. incombination, as 15 5 ends and bearing against the shoulders g atdescribed.

their hinged ends, as described.

2. The combination, with the frame D, hav- EDVARD OWEN.

ing notched side bars, a a, of the bar b, provided with transverse pinsh, adapted to re- Vitnesses: o ceive a lever for elevating the frame D,as de- THOS. CLARK,

scribed. W. H. 'BRUTON.

